Claim · model-written summary
The authors propose a glucose-specific effect on nitrate uptake due to glucose presence rather than respiration.
- Taxon
- dwarf beant0
- Compound
- glucosee0
- Outcome
- NO 3 − uptakee0
- Qualifier
- rather than to its utilization in root respiratione0
Not reportedMaterialGeneOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentComparatorSettingDirectionValue
Verbatim
e0“we propose a glucose‐specific effect on NO 3 − uptake that is due to the presence of glucose rather than to its utilization in root respiration”
t0“dwarf bean”
Title
Role of sugars in nitrate utilization by roots of dwarf bean
Charlotte H. Hänisch ten Cate; Hans Breteler Physiologia Plantarum 1981. doi:10.1111/j.1399-3054.1981.tb06045.x
Other claims from this paper (17)
- Association Sugar status did not influence the apparent induction pattern of nitrate uptake.
- Observation After 6 hours, steady-state nitrate uptake ranked intact above dark, ringed and excised plants.
- Observation After 6 hours, root nitrate reductase activity ranked intact above dark, ringed and excised plants.
- Intervention effect Exogenous sucrose restored nitrate reductase activity in excised roots to intact plant levels.
- Intervention effect Sucrose did not fully restore nitrate uptake in excised roots.
- Intervention effect Decapitation after nitrate pretreatment caused net uptake to decline and become negative after three hours.
- Intervention effect Exogenous fructose slowed the decline in net nitrate uptake after decapitation.
- Intervention effect Glucose rapidly stimulated nitrate uptake, sometimes within five minutes.
- Intervention effect Excised-root nitrate reductase activity was higher with glucose than fructose after six hours.
- Observation Glucose and fructose stimulated oxygen consumption equally.
- Observation Glucose and fructose stimulated labeled carbon dioxide release equally.
- Observation There was no indicated differential glucose–fructose effect on nitrate reductase independent of nitrate uptake.
- Observation Nitrate-induced roots maintained constant nitrate reductase activity.
- Intervention effect Removing nitrate caused exponential nitrate reductase decay with a roughly 12-hour half-life in intact plants.
- Intervention effect Removing nitrate caused exponential nitrate reductase decay with a 5.5-hour half-life in excised roots.
- Observation Roots excised with nitrate present also had a 5.5-hour nitrate reductase decay half-life.
- Mechanism The authors infer that sugar status primarily sets the apparent nitrate reductase decay rate in excised roots.